/**
 * @file
 * Ethernet Interface Skeleton
 *
 */

/*
 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 *
 * Author: Adam Dunkels <adam@sics.se>
 *
 */

/*
 * This file is a skeleton for developing Ethernet network interface
 * drivers for lwIP. Add code to the low_level functions and do a
 * search-and-replace for the word "ethernetif" to replace it with
 * something that better describes your network interface.
 */

#include "lwip/opt.h"

#if 1 /* don't build, this is only a skeleton, see previous comment */

#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/pbuf.h"
#include "lwip/stats.h"
#include "lwip/snmp.h"
#include "lwip/ethip6.h"
#include "lwip/etharp.h"
#include "netif/ppp/pppoe.h"
#include "lwip_comm.h"

/* Define those to better describe your network interface. */
#define IFNAME0 'e'
#define IFNAME1 'n'

/**
 * Helper struct to hold private data used to operate your ethernet interface.
 * Keeping the ethernet address of the MAC in this struct is not necessary
 * as it is already kept in the struct netif.
 * But this is only an example, anyway...
 */
struct ethernetif {
  struct eth_addr *ethaddr;
  /* Add whatever per-interface state that is needed here. */
};

/* Forward declarations. */
err_t  ethernetif_input(struct netif *netif);

/**
 * In this function, the hardware should be initialized.
 * Called from ethernetif_init().
 *
 * @param netif the already initialized lwip network interface structure
 *        for this ethernetif
 */
static err_t
low_level_init(struct netif *netif)
{
  #ifdef CHECKSUM_BY_HARDWARE
	int i;
	#endif

	netif->hwaddr_len = ETHARP_HWADDR_LEN;

	netif->hwaddr[0] = lwipdev.mac[0]; 
	netif->hwaddr[1] = lwipdev.mac[1]; 
	netif->hwaddr[2] = lwipdev.mac[2];
	netif->hwaddr[3] = lwipdev.mac[3];
	netif->hwaddr[4] = lwipdev.mac[4];
	netif->hwaddr[5] = lwipdev.mac[5];
	netif->mtu = 1500;

	netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP;
	
	ETH_MACAddressConfig(ETH_MAC_Address0, netif->hwaddr);
	ETH_DMATxDescChainInit(DMATxDscrTab, Tx_Buff, ETH_TXBUFNB);
	ETH_DMARxDescChainInit(DMARxDscrTab, Rx_Buff, ETH_RXBUFNB);

#ifdef CHECKSUM_BY_HARDWARE
	for (i = 0; i < ETH_TXBUFNB; i++)
	{
		ETH_DMATxDescChecksumInsertionConfig(&DMATxDscrTab[i], ETH_DMATxDesc_ChecksumTCPUDPICMPFull);
	}
#endif

	ETH_Start();

	return ERR_OK;
}

/**
 * This function should do the actual transmission of the packet. The packet is
 * contained in the pbuf that is passed to the function. This pbuf
 * might be chained.
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
 * @return ERR_OK if the packet could be sent
 *         an err_t value if the packet couldn't be sent
 *
 * @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
 *       strange results. You might consider waiting for space in the DMA queue
 *       to become available since the stack doesn't retry to send a packet
 *       dropped because of memory failure (except for the TCP timers).
 */

static err_t
low_level_output(struct netif *netif, struct pbuf *p)
{
  u8 res;
	struct pbuf *q;
	int l = 0;
	u8 *buffer = (u8*)ETH_GetCurrentTxBuffer();
	for (q = p; q != NULL; q = q->next)
	{
		memcpy((u8_t*)&buffer[l], q->payload, q->len);
		l = l + q->len;
	}
	res = ETH_Tx_Packet(l);
	if (res == ETH_ERROR)
		return ERR_MEM;
	return ERR_OK;
}

/**
 * Should allocate a pbuf and transfer the bytes of the incoming
 * packet from the interface into the pbuf.
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @return a pbuf filled with the received packet (including MAC header)
 *         NULL on memory error
 */
static struct pbuf *
low_level_input(struct netif *netif)
{
  struct pbuf *p, *q;
	u16_t len;
	int l = 0;
	FrameTypeDef frame;
	u8 *buffer;
	p = NULL;

	frame = ETH_Rx_Packet();
	len = frame.length;
	buffer = (u8*)frame.buffer;
	p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
	if (p != NULL)
	{
		for (q = p; q != NULL; q = q->next)
		{
			memcpy((u8_t*)q->payload, (u8_t*)&buffer[l], q->len);
			l = l + q->len;
		}
	}
	frame.descriptor->Status = ETH_DMARxDesc_OWN;
	if((ETH->DMASR & ETH_DMASR_RBUS) != (u32)RESET)
	{ 
		ETH->DMASR = ETH_DMASR_RBUS;
		ETH->DMARPDR = 0;
	}
	return p;
}

/**
 * This function should be called when a packet is ready to be read
 * from the interface. It uses the function low_level_input() that
 * should handle the actual reception of bytes from the network
 * interface. Then the type of the received packet is determined and
 * the appropriate input function is called.
 *
 * @param netif the lwip network interface structure for this ethernetif
 */
err_t ethernetif_input(struct netif *netif)
{
	err_t err;
	struct pbuf *p;
	p = low_level_input(netif);
	if (p == NULL)
		return ERR_MEM;
	err = netif->input(p, netif);
	if (err != ERR_OK)
	{
		LWIP_DEBUGF(NETIF_DEBUG,("ethernetif_input: IP input error\n"));
		pbuf_free(p);
		p = NULL;
	}
	return err;
}

/**
 * Should be called at the beginning of the program to set up the
 * network interface. It calls the function low_level_init() to do the
 * actual setup of the hardware.
 *
 * This function should be passed as a parameter to netif_add().
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @return ERR_OK if the loopif is initialized
 *         ERR_MEM if private data couldn't be allocated
 *         any other err_t on error
 */
err_t
ethernetif_init(struct netif *netif)
{
  LWIP_ASSERT("netif!=NULL", (netif != NULL));
#if LWIP_NETIF_HOSTNAME
	netif->hostname = "lwip";
#endif 
	netif->name[0] = IFNAME0;
	netif->name[1] = IFNAME1;
	netif->output = etharp_output;
	netif->linkoutput = low_level_output;
	low_level_init(netif);

	return ERR_OK;
}

#endif /* 0 */
